get rid of the hack that prevents ~foo~ from being converted to <del>

Author: yihui

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: litedown
 Type: Package
 Title: A Lightweight Version of R Markdown
-Version: 0.6.3
+Version: 0.6.4
 Authors@R: c(
     person("Yihui", "Xie", role = c("aut", "cre"), email = "[email protected]", comment = c(ORCID = "0000-0003-0645-5666", URL = "https://yihui.org")),
     person("Tim", "Taylor", role = "ctb", comment = c(ORCID = "0000-0002-8587-7113")),
@@ -21,7 +21,7 @@ Description: Render R Markdown to Markdown (without using 'knitr'), and Markdown
 Depends: R (>= 3.2.0)
 Imports:
     utils,
-    commonmark (>= 1.9.1),
+    commonmark (>= 1.9.5),
     xfun (>= 0.51)
 Suggests:
     rbibutils,

R/mark.R

@@ -178,13 +178,6 @@ mark = function(input, output = NULL, text = NULL, options = NULL, meta = list()
       sprintf('!%s!', x)
     })
   }
-  # TODO: remove this after commonmark > 1.9.2 is on CRAN
-  # disallow single tilde for <del> (I think it is an awful idea in GFM's
-  # strikethrough extension to allow both single and double tilde for <del>)
-  find_prose()
-  text[p] = match_replace(text[p], r3, function(x) {
-    gsub('^~|~$', '\\\\~', x)
-  })
   # add line breaks before/after fenced Div's to wrap ::: tokens into separate
   # paragraphs or code blocks
   text[p] = sub('^([ >]*:::+ )([^ {]+)$', '\\1{.\\2}', text[p]) # ::: foo -> ::: {.foo}